1. Field of the Invention
The present invention relates to support structures used in conjunction with spacecrafts such as satellites or the like, and more particularly to a deployable support structure which is stowed adjacent to a satellite during launch and which is deployed into an operating position upon attainment of orbit by the satellite.
2. Description of the Prior Art
The size and weight of space vehicles in general, and especially satellites, must be minimized for launch and for space operations where limited power is available. Therefore, any procedure or configuration which can be used to minimize weight and maximize the compactness of a structure is desirable. Aside from these two goals, considerations pertaining to weight distribution assuring proper balance are also important.
In an effort to satisfy all of these requirements, various deployment mechanisms and booms have been suggested in the prior art. One such attempt is shown in U.S. Pat. No. 3,326,497 issued to J. P. Michelson on June 20, 1967 which discloses a solar cell array wherein hingeably affixed panels are deployed by a plurality of motor drives cooperating with the hinges affixing the panels together. The motor drives are electrically powered and therefore add to the overall power consumption of the vehicle to which the array is mounted. In addition, since a plurality motor drives are employed, this multiplicity adds to overall weight.
U.S. Pat. No. 3,525,483 issued to E. M. Van Alstyne on Aug. 25, 1970 discloses a deployment mechanism which comprises a plurality of a spring hinged panels which are cabled together by a cable and pulley arrangement. An electric motor drive is employed to move the cable so that the pulleys are rotated causing the panels to be extended. As in Michelson, the weight and the power consumption of an electric motor drive is not avoided.
U.S. Pat. No. 3,620,846 issued to T. O. Payne on Nov. 16, 1971 shows a deployable cell array which includes a plurality of independent modules each having a panel formed of a plurality of trapezoidal panel segments. A linear actuator is used to move the trapezoidal panel segments along an articulated track while a telescoping driven member is simultaneously employed to extend and therefore erect the trapezoidal sections.
The present invention eliminates the need for an electrically-powered motor drive and therefore eliminates the attendant power consumption and weight problems. The configuration of the present invention is therefore optimum since it also satisfies the needs of compactness and balance.